“This day have I perfected your religion for you; completed my favor upon you; and have chosen for you Islam as your religion.”
One of the great virtues of Hajj is that the verse announcing the completion of the Deen was revealed at the time of Hajj. Hazrat Imaam Ghazali R.A. writes in his ‘Ilyas’: Hajj is one of the fundamental principles of Islam. Upon it the foundation of Islam became completed and upon it the Deen was completed. It was at the time of Hajj that this Ayah was revealed.
Once a learned person from among the Jews said to Hazrat Umar R.A.: “In the Quran you people read a certain verse, if that verse had been revealed to us, we would have celebrated that day annually.” Hazrat Umar R.A. inquired: “which verse is that?” He replied: “Al Yowma akmaltu lakum Deenakum.” (The verse under discussion) Hazrat Umar R.A. said “Verily I remember the day and the place where this verse was revealed (and apart from the revelation of this verse, which was on a Friday) it was already a double celebration for us. Firstly it was Friday-a day of celebration for all Muslims and secondly, it was the day of Arafat – a day of celebration for the pilgrims. Hazrat Umar R.A. further stated that this verse was revealed on a Friday after Asar on the day of Arafat while Rasulullah (Sallallaho Alaihi Wassallam) was seated on his she-camel. It is further stated in the Hadith that no further verses were revealed after this one with regard to Halaal and Haraam. When this verse was revealed Rasulullah (Sallallaho Alaihi Wassallam) was seated on his she-camel. The camel was forced to sit down because of the great weight descending upon it on account of the revelation. This is what normally happened. Hazrat Ayesha R.A. states that, when Rasulullah (Sallallaho Alaihi Wassallam) was seated on a camel, the camel used to lower its neck being unable to lift it or move a step until revelation had ended. Hazrat Abdullah Ibn Umar R.A. relates from Rasulullah (Sallallaho Alaihi Wassallam) that when revelation descended upon him he feared that he would loose his life. (Durre Mansoor) Hazrat Zaid Ibn Thabit R.A. states that when the verse 95 in Surah 4 was being revealed I was sitting next to Rasulullah (Sallallaho Alaihi Wassallam). Rasulullah (Sallallaho Alaihi Wassallam) then became like one in a state of semi consciousness, and he put his high upon mine, the weight of which was so great that I felt that my leg would break. (Durre Mansoor) this was due to the greatest of Allah’s words, which we now a days read very casually and superficially as though it were ordinary speech.